Improvement in bit-stocks



' M. BoYNToN.

BIT-STOCK..

'Patented May 9, 1876.V

UNTTiirD STATES PATENT OFFICE- EBEN M. BOYNTON, OF NEW YORK, N. Y.

vnuPROvt-lwENT INVBlT-sTOcKs. I

Specification forming part of Letters Patent N o. 177,089, dated May 9, 1876; application led v Y February 14, 1876.

` made to clasp thebit or tool, all as hereinaftery more fully described.

Figure lis a side elevation'rof a bit-stock complete, made on my'plan. Figs. 2 and 3 are longitudinal sections of the head'and operating parts, the former showing the tool released and the latter showing it held in place. Fig. 4 is an endview. Y

In constructing a bit-stock 0n my plan I make the body in any ofthe usual styles, and to the end in which the tool is inserted secure a head or socket piece, A, which has a'rect angular taper socket, O, to receive the corre sponding shank or end of the bit I, as shown in Figs. 2 and 3. The end of this head A is extended out beyond. the socket O, and is made circular in cross-section, with its extremity made more or less belhmouthed, as shown in Figs. 2 and 3. I then provide a tubular cap, B, which ig tted to `screw on the head A, as shown, it having at its outer end, on opposite sides, two lugs, y,onits interior, between which I pivot the clamping-jaws D on pins e, as shown in'Figs. 2 and 3. l'These jaws D are made ot' such a length that, when turned to the position shown in Fig. 3, they will grasp between their ends the stem of a bitl I, which may be inserted in the head, their outer and upper portions being made cam-shaped also, so th'at, when turned to a certain extent, they will lock or bear against the outer walls of the cap B, thereby preventing them from turning far enough to permit their loose ends to pass beyond a horizontal line at right angles to the axis of the head. 'Ihe ends of these jaws vD are made concave, or with a notch in them, so that, when crowded against a bit v or tool, they will clasp it and hold it centrally` i between-them.

As shown in Fig. 2, it'will` be seen that the cap B is screwed o" far enough vto permit the- 4 4 jaws D to hang loose without contact. with' .the tubular end of the head-piece A, and when in that position the bit I can be insertedbetween the jaws, as represented in dotted lines,

and seated in the socket O. As the cap B is screwed on, the end of the` tubular vpart C of the head-piece A presses against the inclined outer sides of the jaws D, thereby forcing them inward, and causing their ends to close against and grasp the bit I between them, as represented-in Fig.,3..

To remove the bit it is only necessary .to screw the cap oft' far enough to releasethe jaws D.

It will be seen bits or tools of any'size, from the largest to the Asmallest usuallymade, and that is Very simple and'cheap to make. Y n

I am aware that pivoted jaws `have been arranged in the screw-cap ot' a bit-stock,` as in the patent of C. H. Stockbridge, February 19,

1867 5 nbut in that the jaws are .made long, so f as to hold simply by fitting over the shoulders of the bit, and not by grasping the stem between them, as in my case. I therefore dol not claim the pivoted jaws, broadly but What I do claim is- In combination with the head-piece A, having a socket, O, for receiving'the tool, the short pivoted jaws D, constructed and arranged to grasp the tool between their ends,

substantially as shown and described.

EBEN M. BOYNTON. Witnesses:

P. T. DODGE,

W. O. Donau.`

that by this constructionI produce a bit-stock that willfcenter and hold Y 

